Dementia is a general term used to describe a decline in cognitive function. It is not a single disease but rather, an end product of multiple diseases that lead to cognitive failure of the brain. These disorders (e.g. Alzheimer’s disease, stroke) are caused by abnormal brain changes and trigger a deterioration in memory, thinking skills, behaviour, comprehension and judgement. They also affect emotional control, feelings, relationships and can impair daily life. The impact of dementia can often be overwhelming to not just people who have it, but their family members and loved ones too.
There are various causes of dementia, the 2 most common worldwide and in Singapore are
Alzheimer’s disease and Vascular dementia.
Alzheimer’s Disease —which accounts for about 60-80% of dementia cases—
is thought to be caused by an accumulation of abnormal protein plaques and neurofibrillary tangles in the brain. This causes damage to brain cells and hinders the cells’ ability to communicate with each other properly. The result is a malfunction in thinking, behaviour and feelings. Due to the nature of the illness, Alzheimer’s sufferers tend to experience a slow gradual decline in their cognitive abilities.
Vascular dementia is caused by disease of the blood vessels supplying the brain. Impaired blood flow to the brain cells causes impairment of neuronal function and a decline in a person’s cognitive ability. The most obvious way this can happen is during strokes, where brain cells die as they are deprived of blood flow. A single small stroke in a strategic area or multiple or large strokes can disrupt brain circuits and lead to problems with cognition.
Often, these 2 processes are often seen together in one person, and this is then termed a “Mixed Dementia”.
Dementia affects each person differently, depending on the severity of the disease and even the person’s personality. We usually identify dementia according to 3 stages.
Dementia is often progressive, which means symptoms start out slowly and are often overlooked, especially in the early stages. If you or someone you know is experiencing any of the symptoms above, please see a neurologist to determine the cause and seek treatment. In severe cases, dementia can progress to a vegetative state. Being diagnosed ahead of time allows you to plan for the future.
In Singapore, 1 in 10 people aged 60 and above may have dementia. Although ageing is commonly associated with dementia and is the greatest risk known factor for dementia, dementia is not a normal part of ageing.
Other risk factors for dementia include:
If you have a family history of Alzheimer’s disease, you are generally considered to be at a heightened risk of Alzheimer’s. However, in most cases, it is almost impossible to predict a person’s risk just based on their family history alone. Many individuals with a family history of Alzheimer’s never develop the disease and vice versa.
With that said, Down’s syndrome has been shown to display neurological and behavioural changes similar to Alzheimer’s by the time patients reach middle age.
Atherosclerosis is the buildup of plaque and other matter in the inner lining of the artery. It is a significant risk factor for vascular dementia because it compromises delivery of blood to the brain, which can ultimately cause a stroke. Activities like smoking drastically increases your risk of atherosclerosis.
Research has linked high levels of low-density lipoprotein (LDL) to Alzheimer’s disease and vascular dementia.
Diabetes is known to contribute to atherosclerosis and stroke, both of which are risk factors for vascular dementia.
We diagnose the type of dementia based on a series of tests; including accessing your medical history carefully, conducting a mental status exam, and sending you for lab tests and brain scans. You may be sent for health tests to check for things like vitamin deficiencies and infections as many medical conditions can cause cognitive impairment.
Brain imaging tests like CT and MRI scans are frequently performed to look brain tumours, strokes as well as areas of brain atrophy which may be seen in Alzheimer’s Disease.
Treatment for dementia depends on its cause. Although in most cases, there is no cure for dementia; appropriate therapy can improve mental function and patient’s quality of life...
In addition to medications, holistic treatment of dementia includes a care plan with diet, exercise and social interaction. This was shown to be effective in Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) study and proves that a multi domain lifestyle intervention is beneficial for prevention of cognitive decline.